A Method for Reducing the Tooth Profile Errors of the Spur Gears in the Hobbing Process

The gear hobbing process is one of the most common and economical methods to machine the involute gear. The tooth profile deviations of the hobbed gears were caused by machine errors, hob errors and the deviation of the setting operations. In the paper, the influences of the run out of hob and the hob lead error on the tooth profile deviations of gears are analyzed through the position deviations of the generated point Pk on the cutting edge versus the surface of the imaginary rack. This report also proposes the method reducing the tooth profile deviations by adjusting the run out of hob suitable for the hob lead errors. The test result shows the effectiveness in decreasing the tooth profile deviations of hobbed gears.